Tip part assembly for an endoscope

ABSTRACT

A method of manufacture of a tip part assembly for an endoscope having a proximal end and a distal end opposite from the proximal end, the method including: providing a bending section having a proximal end and a distal end, providing a camera assembly including a camera module, providing a substantially tubular circumferential wall having a proximal end and a distal end opposite from the proximal end, providing a distal end wall, arranging the camera module to be held by or attached to the distal end wall, manufacturing a housing by adjoining the distal end wall to the distal end of the circumferential wall, the housing including the circumferential wall and the distal end wall and enclosing a spacing that houses at least a portion of the camera module, and adjoining the distal end of the bending section and the proximal end of the housing.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from, and the benefit of,European Patent Application Nos. 19195989.9, 19195995.6, 19195996.4, and19195998.0, filed Sep. 6, 2019, which applications are incorporated byreference herein in their entirety.

Commonly owned U.S. patent application Ser. Nos. 17/013,519, 17/013,445,and 17/013,463, filed concurrently with the present application, claimpriority from European Patent Application Nos. 19195989.9, 19195995.6,19195996.4, and 19195998.0, and are incorporated by reference herein intheir entirety.

TECHNICAL FIELD

The present disclosure relates to endoscopes and more specifically to atip part assembly for an endoscope.

BACKGROUND

Endoscopes are well known for visually inspecting difficult to accessplaces such as human body cavities. Typically, the endoscope comprisesan elongated insertion tube with a handle at the proximal end, as seenfrom the operator, and visual inspection means, such as a built-incamera, at the distal end of the elongated insertion tube. Thisdefinition of the terms distal and proximal, i.e. proximal being the endclosest to the operator and distal being the end remote from theoperator, as used herein for endoscopes in general, is adhered to in thepresent specification.

As the name indicates, endoscopes are used for seeing inside things,such as lungs or other human body cavities of a patient. Modernendoscopes are therefore typically equipped with a light source and avision receptor including a vision sensor, such as a camera or an imagesensor. Provided that sufficient light is present, it is possible forthe operator to see where the endoscope is steered and to set the targetof interest once the tip has been advanced thereto. This thereforenormally requires illumination of the area in front of the distal tip ofthe endoscope, in particular the field of vision of the camera(s). Thelight source, such as a light emitting diode, LED, or an optical fibre,may provide illumination.

Electrical wiring for the camera and other electronics, such as LEDlighting accommodated in the tip part assembly at the distal end, runalong the inside of the elongated insertion tube from the handle to thetip part assembly. Instead of using cameras, endoscopes may also befibre-optic, in which case the optical fibres run along the inside ofthe elongated insertion tube to the tip part assembly. For someapplications, a working or suction channel may run along the inside ofthe insertion tube from the handle to the tip part assembly, e.g.allowing liquid to be removed from the body cavity or allowing forinsertion of surgical instruments or the like, into the body cavity. Thesuction channel may be connected to a suction connector, typicallypositioned at a handle at the proximal end of the insertion tube. Forother applications, the working or suction channel may be omitted.

In order to be able to manoeuvre the endoscope inside the body cavity,the distal end of the endoscope may comprise a bending section withincreased flexibility, e.g. an articulated tip part assembly allowingthe operator to bend this section. Typically, this is done by tensioningor slacking steering wires also running along the inside of theelongated insertion tube from the articulated tip part assembly to acontrol mechanism of the handle.

Some prior art tip part assemblies include a housing, in a spacing ofwhich a camera assembly is positioned. Such housings are manufactured,typically molded, in one or more pieces and typically include an outeror external surface for facing the environment, although part of thisouter surface may be covered by a flexible sleeve. If the housing is inmore pieces, the pieces are typically assembled before components of thetip parts assembly, such as a camera module, are positioned within thehousing.

For some types of endoscopes, such as uretheroscope, there is a desireto provide the tip part assembly of the endoscope with a smallerdiameter or cross sectional extent, especially where the tip partassembly is to be inserted into narrower body cavities. In very narrowbody cavities, even a reduction of 1 mm or less in the cross-sectionalextent of a tip part assembly can have a noticeable effect on thecomfort of the patient and may even make it possible to reach body areasnot otherwise accessible. Providing a small size of the tip partassembly can especially be a challenge in cases where the endoscopecomprises both a camera and a working channel extending through the tippart assembly since the camera and working channel are positioned oneabove the other within the tip part assembly, which takes up space in aradial direction of the tip part assembly.

A general desire in the field of endoscopy is to electrically insulatethe insertion tube, and thus especially the tip part assembly, from theoutside, so as to mitigate the risk of an insulation breakdown and aresulting excessive leakage current.

A desire of the methods and the tip part assemblies according to thisdisclosure may be to provide and easy assembly and/or reduce the cost ofassembly of a tip part assembly and/or to allow for use of a broaderrange of materials and/or to enable use of less materials in parts of atip part assembly.

It is therefore desirable to provide a tip part assembly with smallerdimensions for an endoscope, such as an uretheroscope, havingelectrically insulating properties and being structurally stable.

SUMMARY

On this background, an object of the methods and the tip part assembliesmay be to mitigate one or more of these desires.

A first embodiment of a first aspect of this disclosure relates to amethod of manufacture of a tip part assembly for an endoscope, the tippart assembly having a proximal end for being connected to other partsof the endoscope and a distal end positioned oppositely from theproximal end, the method comprising the steps of: a) providing abendable bending section, the bending section including a proximal endand a distal end, b) providing a camera assembly comprising a cameramodule, c) providing a substantially tubular circumferential wall, thecircumferential wall comprising a proximal end and a distal end, thecircumferential wall proximal end being positioned oppositely from thecircumferential wall distal end, d) providing a distal end wall, e)arranging the camera module so that the camera module is held by orattached to the distal end wall, f) subsequent to step e), manufacturinga housing of the tip part assembly by adjoining the distal end wall tothe distal end of the circumferential wall so that the housing comprisesthe circumferential wall and the distal end wall, and so that thecircumferential wall and the distal end wall enclose a spacing, at leasta portion of the camera module being housed in the spacing, and g)subsequent to step f), adjoining the distal end of the bending sectionand the proximal end of the housing, so that the tip part assemblycomprises the bending section, the camera assembly, and the housing, thecamera assembly being at least partly housed in the spacing, the distalend wall being positioned at the distal end of the tip part assembly.

A second aspect relates to a method of manufacture of a tip partassembly for an endoscope, the tip part assembly having a proximal endfor being connected to other parts of the endoscope and a distal endpositioned oppositely from the proximal end, the method comprising thesteps of: a) providing a bendable bending section, the bending sectionincluding a proximal end and a distal end, b) providing a cameraassembly comprising a camera module, c) extruding a substantiallytubular circumferential wall, the circumferential wall comprising aproximal end and a distal end, the circumferential wall proximal endbeing positioned oppositely from the circumferential wall distal end, d)providing a distal end wall, e) arranging the camera module so that thecamera module is held by or attached to the distal end wall, f)manufacturing a housing of the tip part assembly by adjoining the distalend wall to the distal end of the circumferential wall so that thehousing comprises the circumferential wall and the distal end wall, andso that the circumferential wall and the distal end wall enclose aspacing, and g) adjoining the distal end of the bending section and theproximal end of the housing, so that the tip part assembly comprises thebending section, the camera assembly, and the housing, the cameraassembly being at least partly housed in the spacing, the distal endwall being positioned at the distal end of the tip part assembly.

The methods according to this disclosure may include that attachment ofthe camera module to the distal end wall occurs before thecircumferential wall is adjoined with the distal end wall. This may makeit easier, e.g. for an assembler, to attach the camera module since morespace may be available when the circumferential wall is not yet providedto enclose the camera module. This may again ensure that the cameramodule is correctly positioned with respect to the other parts of thetip part assembly. The methods according to this disclosure may includethat the camera assembly further comprises a circuit board in electricalconnection with the camera module.

The methods according to this disclosure may also provide more freedomof choice of method of manufacture of the circumferential wall. Forexample, it may be possible to manufacture the circumferential in anextrusion process. Extrusion processes typically have the advantage,e.g. compared to molding processes, that a very well-definedcross-sectional profile of the extruded object can be obtained. Sincetolerances are then smaller, extruding the circumferential wall mayentail that the circumferential wall can be made with a thin wallthickness without compromising insulation and structural stability ofthe housing. This means that the overall cross-sectional dimensions ofthe tip part assembly can also be made smaller. Furthermore,circumferential wall material may be saved, and electrical insulation ofthe circumferential wall and the housing may be more secure. Extrudedobjects are often also more structurally stable so that increasedstructural stability of the circumferential wall and/or housing and/ortip part assembly can potentially be achieved.

Compared to solutions where a light guide is molded in one piece with acircumferential wall or a housing, the methods according to thisdisclosure may also make it possible to increase a length andflexibility of the circumferential wall, which can allow for thecircumferential wall to form part of or cover at least part of thebending section of the tip part assembly.

Compared to solutions where a light guide is molded in one piece with acircumferential wall or a housing, the methods according to thisdisclosure may also make it possible to increase size or dimensions ofthe light guide and/or provide more freedom regarding positioningthereof, see further below.

Step d) of the methods according to this disclosure may alternatively oradditionally include extruding a tubular or substantially tubularcircumferential wall part, wherein at least a part of thecircumferential wall part forms the circumferential wall of the housing.For example, a long circumferential wall part may be extruded, and oneor more circumferential walls may be cut from the long circumferentialwall part.

The term “endoscope” may be defined as a device suitable for examinationof natural and/or artificial body openings, e.g. for exploration of alung cavity. Additionally, or alternatively, the term “endoscope” may bedefined as a medical device.

The embodiments of this disclosure may comprise the bending section maycomprise a number of hingedly interconnected segments including thedistal end segment, a proximal end segment, and a plurality ofintermediate segments positioned between the proximal end segment andthe distal end segment. At least one hinge member may interconnectadjacent segments with each other. The bending section may be a sectionallowing the tip part assembly to bend relative to an insertion tube,potentially so as to allow an operator to manipulate the tip partassembly while inserted into a body cavity of a patient. The bendingsection may be molded in one piece or may be constituted by a pluralityof molded pieces.

The bending section may or may not be attached to the housing byintroducing a holder ring therebetween as is known in the art. Anadhesive may be separately applied to attach the bending section endsegment to the housing or, if a holder ring is present, to attach thedistal end segment and the housing to the holder ring.

The circumferential wall may be an outer or exterior wall and mayinclude an outer surface of the tip part assembly for facing theenvironment. Potentially, no parts of or only a sleeve of the tip partassembly are positioned outside an outer circumference of thecircumferential wall.

Manufacture of the circumferential wall may include extrusion of thecircumferential wall or a circumferential wall part through a die, thedie potentially having a ring-shaped cross section.

The circumferential wall may have a length in a longitudinal directionin the range of 3-15, such as 5-10 mm. This longitudinal direction mayextend along a centre axis of the circumferential wall and/or may extendfrom the proximal towards the distal end of the tip part assembly.

The circumferential wall may extend to at least partly cover or enclosethe bending section and/or a bending section distal end segment. Thecircumferential wall may extend to at least partly cover or enclose thebending section or a bending section distal end segment. Thecircumferential wall may be flexible and/or bendable, potentiallyallowing the circumferential wall to follow bending of the bendingsection, especially if the circumferential wall is positioned to coverat least part of the bending section.

The circumferential wall may define an outer surface of the tip partassembly, potentially at least partly covered by a sleeve, the sleevepotentially extending along at least part of an outer surface of thebending section and the circumferential wall.

A wall thickness of the circumferential wall may be less than 0.25, 0.2,0.15, 0.14, or 0.13 mm. This may be achieved by extruding thecircumferential wall.

The circumferential wall may be provided separately from or non-integralwith the distal end wall before they are adjoined.

In step e) of the methods of this disclosure, the circumferential wallmay be positioned away from or at a distance from the distal end wall orso that the circumferential wall does not enclose the camera module, thecamera assembly, or any other components of the tip part assembly, whichmay allow for more space around the camera module and distal end wallduring step e).

The circumferential wall may comprise or consist or substantiallyconsist of: ABS (Acrylonitrile-Butadine-Styrene), Acrylic, EVA(Ethylene-Vinyl-Acetate), Flexible PVC (Poly Vinyl Chloride), HDPE (HighDensity Polyethylene), LDPE (Low Density Polyethylene), PC(Polycarbonate), PP (Polypropylene), PU (Polyurethane), Rigid PVC (PolyVinyl Chloride), TPE (Thermoplastic elastomers) or combinations thereof.The distal end wall may comprise or consist or substantially consist ofthe same material as listed for the circumferential wall.

Adjoining may be performed by means of an adhesive, which may be appliedto the distal end of the bending section and/or to the proximal end ofthe housing. The adhesive used to adjoin the distal end of the bendingsection and the proximal end of the housing may be the same types ofadhesive as the one used to adjoin the distal end wall and thecircumferential wall.

The housing and/or circumferential wall and/or distal end wall may be ofor comprise an electrically insulating and/or a transparent material.The housing and/or circumferential wall and/or distal end wall may be ofor comprise plastic materials, polymers or plastic polymers. Thetransparent material may comprise or consist or substantially consist ofa transparent plastic or plastic polymer material, such as: apolycarbonate (PC) polymethylmethacrylate (PMMA), PolyethyleneTerephthalate (PET), Amorphous Copolyester (PETG), Polyvinyl Chloride(PVC), Liquid Silicone Rubber (LSR), Polyethylene (PE), FluorinatedEthylene Propylene (FEP), Styrene Methyl Methacrylate (SMMA), StyreneAcrylonitrile Resin (SAN) and/or Methyl Methacrylate AcrylonitrileButadiene Styrene (MABS) or combinations thereof. Alternatively oradditionally, they made be of or comprise a metal.

The distal end wall and the circumferential wall may be of or maycomprise different materials.

The distal end wall may be positioned at the distal end of the assembledtip part assembly. The distal end wall may comprise a holding sectionfor holding the camera module, the camera module in step e) beingattached to and/or held in the holding section. The holding section mayinclude an opening or hole in the distal end wall, which opening may berectangular and/or may be shaped to correspond to an outer surface ofthe camera module at the distal end of the camera module. The cameramodule distal end may be arranged in the opening in step e), potentiallyby sliding the camera module distal end into the opening, potentiallyfrom a rear or proximal end of the opening and/or potentially in alongitudinal, distal direction. Alternatively, a distal front surface ofthe camera module may be provided proximally of the distal end wall,potentially adjacent to or abutting a distal end wall proximal surface,whereby the distal end wall may not include a camera module opening, butrather extends in front of the camera module distal end surface. In thiscase, the distal end wall may be transparent to allow light to shinethrough the distal end wall into the camera module.

A holding bracket may extend from a distal end wall proximal surface toenclose at least part of the camera module, and may potentially extendalong one or more side surfaces of the came module. A backstop may beprovided e.g. on inner surfaces of the opening. Such a backstop may stopthe camera module distal end from being slid through the opening and/ormay allow for the camera module to be properly positioned at a desiredlocation with respect to the distal end wall when being slid into theopening. In a final position of the camera module, a camera module frontsurface, which may be a distal lens front surface, may be positioned ata distance from a distal end wall distal or outer surface or may beplane with a distal end wall distal surface. An adhesive may be appliedor injected into a slot between the camera module distal end and theopening. This adhesive may be applied together with an adhesive appliedwithin the spacing.

The camera assembly may be a sub-assembly of the tip part and maycomprise a camera housing, in which the camera module with the imagesensor and lens stack may be arranged. Outer surfaces of the cameramodule or a camera module housing of the camera module may besubstantially box-shaped and/or parallelepipedal. The camera housing mayhouse at least a part of the lens stack and/or a part of the imagesensor.

The lens stack may be positioned distally of or in front of the imagesensor, may include two or more lenses and may include a proximal lensand a distal lens. The camera module may further comprise a lens barrelwhich may hold and encase the lens stack. The lens stack may be stackedand/or the lens barrel may extend in the longitudinal direction. Aconnection surface may be positioned proximally of or behind the imagesensor. The connection surface may face in a proximal direction. Thelens stack or the lens barrel may have a longitudinally extending centreline, which may be, or may be coinciding with, a centre line of thecamera module.

The at least one lens, potentially the plurality of lenses, may be ofone or more types chosen from the group consisting of: concave, convex,plano-concave, plano-convex, bi-convex, bi-concave.

The circumferential wall may be cylindrical or circular cylindrical orsubstantially cylindrical or circular cylindrical.

The circumferential wall may have a fixed or constant cross-sectionalprofile. This profile may be circular or substantially circular, butother profiles are also possible, e.g. ellipsoid.

The circumferential wall may be tubular and/or pipe-shaped and/ortube-shaped and/or ring-shaped or a ring.

The distal end wall may be provided in step d) as a part separate fromthe circumferential wall, or the distal end wall and the circumferentialwall may in step d) be provided as two separate pieces or not in onepiece.

The distal end wall may be molded.

The electrical connection between the circuit board and the cameramodule may be established in step b) and/or before, during or after anyone of steps e), f), and g).

The circuit board may be a printed circuit board (PCB) or a flexibleprinted circuit (FPC). The housing may be attached to the circuit boardby means of the hardened adhesive. The entire or substantially theentire circuit board may be embedded in the adhesive. The circuit boardmay be in electrical connection with the camera module by a connectionsurface thereof.

FPCs may, throughout this specification, be a single- or double-sidedflexible circuit or a rigid-flex circuit, and may comprise one or morelayers of conductive material and two or more layers of insulatingmaterial, and/or may be a flexible flat cable having one or moreconductors. In some embodiments, the FPC may be connected to a secondflexible printed circuit and/or to a printed circuit board (PCB). A PCBmay comprise one or more cupper layers and one or more layers ofinsulating materials, such as layers of a FR-4 (flame retardant)composite material.

The tip part assembly may comprise the bending section and a tip part,the tip part comprising at least the camera assembly and the housing.

An adhesive may be filled into the spacing of the housing through anopen proximal end of the housing so that the camera assembly is at leastpartly embedded in the adhesive.

The adhesive may be allowed or caused to harden, whereby the adhesiveattaches the housing and the camera assembly to each other.

The adhesive may be a liquid adhesive which may be of low dynamicviscosity, such as a dynamic viscosity below or equal to 200, 150, 120,110 or 100 cP (centipoise, which is equal to mPa*s). This may ensurethat the adhesive reaches all corners or substantially all corners of afree volume of the spacing.

The adhesive may be poured into the spacing. The adhesive may beinjected into the spacing. The adhesive may be poured into the spacingthrough an open proximal end of the housing. The adhesive may beinjected into the spacing through an injection needle or a nozzleinserted through or positioned above an open proximal end of thehousing.

A predefined amount of adhesive corresponding to a desired amount ofadhesive in the spacing may be measured off during filling.Alternatively, or additionally, an upper or top level of the adhesivemay be measured during filling to ensure a predefined amount of adhesiveis filled into the housing.

The adhesive may be or may function as a potting material and may beunhardened or uncured when filling out the spacing. The adhesive may becured after being filled into the spacing.

The adhesive may have electrically insulating properties and/or may be apotting material, e.g. such as disclosed in JP2011200399.

The adhesive and/or potting material may comprise or consist of orsubstantially consist of polyurethane adhesives, silicone adhesives, UVadhesives, thermosetting plastics, silicone rubber gels, epoxy resins,polyurethane, silicone or combinations thereof.

The adhesive and/or potting material may be heat cured, chemicallycured, radiation cured (such as UV light cured) or moisture cured etc.

An electronic cable or electronic wires for connecting the circuit boardto other parts of the endoscope may be at least partly embedded in theadhesive.

The tip part assembly may further include at least one light-emittingdiode or LED for illuminating a target of the endoscope. The at leastone light-emitting diode or LED may be positioned in the spacing beforefilling adhesive into the spacing. The LED(s) may be embedded orsubstantially embedded in the adhesive. The circuit board may include anarm leading to and connected to the at least one LED.

The term “target” or “target area” in the context of this specification,may be understood as an area of interest that the tip part assembly ofthe endoscope is being used to analyze.

The tip part assembly may also include one or more light guides and/orLED lenses for guiding light from respective LED(s) to e.g. a front ordistal end surface or distal end wall of the tip part assembly and/or ahousing thereof. The light guide(s) may extend from the distal end ofthe tip part assembly to a respective LED or a respective set of LEDs.In some embodiments, the light guides are made from a transparentmaterial. The light guide(s) may be molded and/or may comprise a portionabutting the camera assembly and/or be arranged in front of the lensstack.

The LEDs may comprise a light emitting surface. The light emittingsurface(s) may emit light in the proximal-distal direction. The lightemitting surface(s) may be positioned in abutment with the housing,where this is provided, or in abutment with one or more light guides.

If no light guide is present, the LED may be positioned adjacent aproximal end surface of the distal end wall, in which case the adhesivemay not be present between a front surface of the LED and a proximal endof the light guide, or between a front surface of the LED and a proximalsurface of the distal end wall. The light guide may be at least partlyembedded in the adhesive. The light guide may include a light shield, inparticular on a surface of the light guide facing the camera assembly.The light shield may be provided as a layer of colour or a materialcladding with material having a low refraction index on said surface. Insome embodiments the material may be air.

The light guide(s) may be in one piece with the distal end wall or theymay be provided as separate parts that are attached to each other. Thelight guide may be manufactured or provided as a piece separate from thecircumferential wall. Compared to solutions where a light guide ismolded in one piece with a circumferential wall or a housing, this maymake it possible to increase size or dimensions of the light guideand/or provide more freedom regarding positioning thereof since amolding tool may put limitations on e.g. possible dimensions of anairgap between the circumferential wall and the light guide.

Alternatively or additionally, the tip part assembly may comprise atleast one steering section for steering a light guide, wherein the lightguide may comprise light fiber(s). Such a steering section may beprovided in one piece with or separately from, potentially attached to,the distal end wall.

In this specification, a proximal-distal direction may be defined as anaxis extending along the parts of the insertion tube of the endoscope.Adhering to the definition of the terms distal and proximal, i.e.proximal being the end closest to the operator and distal being the endremote from the operator. The proximal-distal direction is notnecessarily straight, for instance, if the insertion tube is bent, thenthe proximal-distal direction follows the curvature of the insertiontube. The proximal-distal direction may for instance be a centre line ofthe insertion tube.

Another embodiment of this disclosure concerns a method according to thefirst embodiment, wherein the method is also according to the secondembodiment.

The steps a) to g) of the first embodiment may overlap or correspond tothe steps a) to g) of the second embodiment.

This embodiment may alternatively be worded as:

A method of manufacture of a tip part assembly for an endoscope, the tippart assembly having a proximal end for being connected to other partsof the endoscope and a distal end positioned oppositely from theproximal end, the method comprising the steps of: a) providing abendable bending section, the bending section including a proximal endand a distal end, b) providing a camera module and a circuit board, c)extruding a substantially tubular circumferential wall, thecircumferential wall comprising a proximal end and a distal end, thecircumferential wall proximal end being positioned oppositely from thecircumferential wall distal end, d) providing a distal end wall, e)arranging the camera module so that the camera module is held by orattached to the distal end wall, f) subsequent to step e), manufacturinga housing of the tip part assembly by adjoining the distal end wall tothe distal end of the circumferential wall so that the housing comprisesthe circumferential wall and the distal end wall, and so that thecircumferential wall and the distal end wall enclose a spacing, at leasta portion of the camera module being housed in the spacing, and g)subsequent to step f), adjoining the distal end of the bending sectionand the proximal end of the housing, so that the tip part assemblycomprises the bending section, a camera assembly, and the housing, thecamera assembly comprising the camera module and the circuit board inelectrical connection with each other and being at least partly housedin the spacing, the distal end wall being positioned at the distal endof the tip part assembly.

This may provide a tip part assembly that is structurally stable andwith high adhesive compatibility.

Another embodiment concerns a method according to the first or secondembodiment, wherein step d) of the first or second embodiment comprisesextruding the circumferential wall part and, subsequently, cutting apiece off of the circumferential wall part so that the piece constitutesthe circumferential wall.

The piece constituting the circumferential wall may also be separatedfrom the circumferential wall part in other ways than cutting. Thecircumferential wall part may be a circumferential wall workpiece or acircumferential wall blank.

This may reduce costs of manufacturing the tip part assembly.

The methods according to this disclosure may further comprise the stepsof:

-   -   providing a working channel of the tip part assembly; and    -   arranging at least a portion of the working channel in the        spacing.

The step of arranging at least a portion of the working channel in thespacing may be performed before or after the step of arranging thecamera module/assembly and/or the step of adjoining the circumferentialwall and the end wall. The step of arranging at least a portion of theworking channel in the spacing may be performed before the step ofadjoining the bending section and the housing.

This may provide a tip part assembly where tools and/or surgicalinstruments may be used, particularly where the tools and/or surgicalinstruments are inserted in the working channel. Liquids or otherobjects may also be extracted through the working channel.

The tip part assembly may further include a working channel extendingthrough the spacing of the housing to a hole or an opening in the endwall. The working channel may extend into and/or through the distal endsegment and/or the bending section. The working channel may extendproximally from the tip part assembly or a bending section thereof,potentially towards the proximal end of the endoscope. The workingchannel may allow liquid to be removed from a body cavity and/or allowinsertion of surgical instruments or the like into the body cavity. Theworking channel may be provided as a channel extending from a proximalend of an endoscope to a distal end of the endoscope to guide a tooland/or to provide suction. A connector and/or a connecting portion maybe provided at the proximal end of the endoscope to allow insertion of atool into the working channel and/or to allow suction to be applied tothe working channel. In some embodiments, the working channel comprisesa built-in or integrated tool at or in the distal tip part assembly.Such a tool may be suitable for grabbing, taking, and/or holdingelements in a part of a patient, in which the endoscope tip part isarranged during use.

The working channel may be tubular or substantially tubular and/or havea circumferentially extending, potentially cylindrical or circularcylindrical or substantially cylindrical or circular cylindrical, outerwall enclosing a working channel spacing. A material thickness of thetubular or substantially tubular wall may be less than or equal to 0.2mm or less than or equal to s 0.15 mm. The working channel may have aninner diameter of 0.8 to 2 mm or 1 to 1.6 mm or 1 to 1.4 mm. A wallthickness of a circumferential wall of the working channel may be 0.1 to0.5 mm.

Similar to as for a holding section for the camera module, the distalend wall may comprise a holding section for holding the working channel,the camera module being attached to and/or held in the holding sectionduring positioning of the working channel. The holding section for theworking channel may similarly include an opening or hole in the distalend wall, which opening may be circular and/or may be shaped tocorrespond to an outer surface of the working channel at a distal end ofthe working channel. The working channel distal end may be arranged inthe opening, potentially by sliding the working channel distal end intothe opening, potentially from a rear or proximal end of the openingand/or potentially in a longitudinal, distal direction. A holdingbracket may extend from a distal end wall proximal surface to enclose atleast part of the working channel, potentially may extend along one ormore side surfaces of the working channel. A backstop may be providede.g. on inner surfaces of the opening. Such a backstop may stop theworking channel distal end from being slid through the opening and/ormay allow for the working channel to be properly positioned at a desiredlocation with respect to the distal end wall when being slid into theopening. In a final position of the working channel, a working channeldistal opening may be positioned at a distance from a distal end walldistal or outer surface or may be plane with a distal end wall distalsurface. An adhesive may be applied or injected into a slot between theworking channel distal end and the opening. This adhesive may be appliedtogether with an adhesive applied within the spacing and/or togetherwith an adhesive applied in connection with the camera module asdescribed above.

The adhesive may be applied along a periphery of the working channel.The adhesive may be applied from a proximal side of the opening(s), e.g.together with an adhesive applied in the spacing, or may be applied froma distal side or from a distal end of the tip part assembly or the ofthe openings. Either of the optional holding sections for the cameramodule and the working channel may be in one piece with the distal endwall, or the holding section(s) and the distal end wall may be providedin separate pieces attached to each other.

The working channel may alternatively be provided in one piece with thecircumferential wall and may be extruded together with thecircumferential wall, potentially as a multi-lumen tube or one tubeprovided within another tube. In this case, a working channel sidesurface can be attached to the circumferential wall at an inner side ofthe circumferential wall. In a cross-section, such an extrudedmulti-lumen tube may include two non-coaxial rings or circles touchingor being connected to each other at one point or section of theirperipheries.

The methods according to this disclosure may further comprise the stepof:

-   -   filling a liquid adhesive into the spacing so that the camera        assembly is at least partly embedded in the adhesive.

The step of filling the liquid adhesive into the spacing may beperformed after the step of adjoining the circumferential wall and thedistal end wall and, where the method comprises the steps of providingand arranging a working channel, after the steps of providing andarranging the working channel.

This may provide a tip part assembly with electrical insulation andstructural stability and rigidity.

An outer maximum extent in a cross-sectional direction of thecircumferential wall may be less than 3.3 mm.

Alternatively, an outer maximum extent in a cross-sectional direction ofthe tip part assembly may be less than 3.3 mm.

This outer maximum extent may be a maximum outer diameter of thecircumferential wall and/or the housing and/or tip part assembly and maybe a maximum cross sectional extent or a maximum diameter of thecircumferential wall and/or the housing of the tip part assembly. Theouter maximum extent may be less than 3.2, 3.1, 3.0. 2.9, 2.8, 2.7, 2.6or 2.5 mm.

This may improve the comfort of the patient when the tip part assemblyis inserted. It may also allow access to areas which were previouslyinaccessible or difficult to access.

A third aspect of this disclosure relates to a tip part assembly for anendoscope, the tip part assembly having a proximal end for beingconnected to other parts of the endoscope and a distal end positionedoppositely from the proximal end, the tip part assembly comprising: abendable bending section, the bending section including a proximal endand a distal end, a camera assembly comprising a camera module, and ahousing comprising an extruded substantially tubular circumferentialwall, the circumferential wall comprising a proximal end and a distalend, the circumferential wall proximal end being positioned oppositelyfrom the circumferential wall distal end, the housing further comprisinga distal end wall positioned at the distal end of the tip part assembly,wherein the distal end of the circumferential wall is adjoined to thedistal end wall so that the circumferential wall and the distal end wallenclose a spacing of the housing, wherein the distal end of the bendingsection is adjoined to the proximal end of the circumferential wall, andwherein the camera assembly is arranged to be at least partly housed inthe spacing.

The tip part assembly for an endoscope according to the third aspect ofthis disclosure may have the same advantages as a tip part assemblyaccording to the methods of the first and second aspects of thisdisclosure.

Any one of the above embodiments and the above individual and combinedstructural features of a tip part assembly manufactured according to themethods of this disclosure may also apply to the tip part assembliesaccording to this disclosure. For example, the circumferential wall maybe circular cylindrical or substantially circular cylindrical orring-shaped.

The tip part assembly may further comprise a working channel, wherein atleast a portion of the working channel is arranged in the spacing.

At least the camera module may be attached or adhered to the housing bymeans of a hardened adhesive positioned within the spacing, the cameramodule being at least partly embedded in the adhesive, the adhesivebeing provided separately from the housing.

The adhesive may adhere the camera assembly and/or the circuit boardand/or the camera module to the circumferential wall and/or to thedistal end wall and/or to the housing.

An outer maximum extent in a cross-sectional direction of the housingmay be less than 3.3 mm.

The distal end wall may further comprise at least one light guide and/orat least one steering section for steering a light guide.

The camera assembly may further comprise a circuit board in electricalconnection with the camera module.

The tip part assembly may be manufactured according to the methods ofthe first aspect of this disclosure.

A fourth aspect of this disclosure relates to an endoscope comprising atip part assembly manufactured according to the first or second aspectof this disclosure or a tip part assembly according to the third aspectof this disclosure.

The endoscope may comprise a control element. The control element may beconfigured to allow an operator to control a tip part assembly of theinsertion tube by at least one steering wire. The control element mayallow bending the tip part assembly in at least one direction,potentially in two directions, the two directions potentially beingopposite. The control element may be accommodated in an operatinghandle. The control element may include a lever allowing an operator tocontrol the control element. The lever may extend outwardly from thecontrol element, potentially through an operating handle. The controlelement may be in the form of a roller or a roller disc.

The endoscope may comprise an operating handle. The operating handle maybe suitable for allowing an operator to grip and to operate theendoscope, potentially with one hand. The operating handle may comprisea handle housing arranged at a proximal end of the insertion tube. Thehandle housing may accommodate the control element.

The insertion tube and/or a distal end thereof and/or the tip partassembly thereof may be suitable for insertion into a body cavity,potentially a kidney, through a body opening, potentially a urinarypassage or a urethra. The body may be a natural and/or artificial body,potentially a human body. The insertion tube may extend from theoperating handle towards a distal end of the endoscope.

Additionally or alternatively, the endoscope may form part of a systemfor visually inspecting otherwise difficult to access places such ashuman body cavities, the system further comprising a monitor. Theendoscope may be connectable to the monitor, and the monitor may allowan operator to view an image captured by the camera assembly of theendoscope.

A person skilled in the art will appreciate that any one or more of theabove aspects of this disclosure and embodiments thereof may be combinedwith any one or more of the other aspects of the disclosure andembodiments thereof.

BRIEF DESCRIPTION OF DRAWINGS

The tip part assemblies and methods will now be described in greaterdetail based on non-limiting exemplary embodiments and with reference tothe drawings, on which:

FIG. 1A shows a perspective view of an endoscope in which a tip partassembly according to the present disclosure is implemented,

FIG. 1B shows a perspective view of a monitor to which the endoscope ofFIG. 1A is connected,

FIG. 2 shows a side view of a bending section of the endoscope of FIG.1A and FIG. 1B,

FIG. 3 shows a perspective view of a camera assembly of a tip partassembly of FIGS. 1A and 1B,

FIG. 4A shows a perspective view of a first embodiment of a tip partassembly of FIGS. 1A and 1B,

FIG. 4B shows a perspective view of a second embodiment of a tip partassembly of FIGS. 1A and 1B,

FIG. 4C shows a perspective view of a third embodiment of a tip partassembly of FIGS. 1A and 1B,

FIG. 4D shows a view onto the distal end of the tip part assembly ofFIG. 4C,

FIG. 4E shows a section view A-A of the tip part assembly of FIG. 4C,

FIG. 4F shows a section view of the tip part assembly of FIG. 4C with anadhesive filled into the spacing

FIG. 5A shows a first embodiment of a distal end wall,

FIG. 5B is a perspective view of the distal end wall of FIG. 5A holdinga camera module and a working channel,

FIG. 5C is a proximal view of the distal end wall of FIGS. 5A and 5Cholding the working channel/tube,

FIG. 6A shows a perspective view of a section of a distal end wall, and

FIG. 6B shows a different perspective view of the distal end wall inFIG. 6A.

DETAILED DESCRIPTION

Referring first to FIG. 1A, an endoscope 1 is shown. The endoscope isdisposable, and not intended to be cleaned and reused. The endoscope 1comprises an elongated insertion tube 3. At the proximal end 3 a of theinsertion tube 3 an operating handle 2 is arranged. The operating handle2 has a control lever 21 for maneuvering a tip part assembly 5 at thedistal end 3 b of the insertion tube 3 by means of a steering wire andbending section 4. A camera assembly 6 is positioned in the tip part 5and is configured to transmit an image signal through a monitor cable 12of the endoscope 1 to a monitor 13.

The tip part assembly 5 has a proximal end 5 a for being connected toother parts of the endoscope 1, and a distal end 5 b positionedoppositely from the proximal end 5 a forming the distal end 3 b of theendoscope 1.

In FIG. 1B, a monitor 11 is shown. The monitor 11 may allow an operatorto view an image captured by the camera assembly 6 of the endoscope 1.The monitor 11 comprises a cable socket 12 to which a monitor cable 13of the endoscope 1 can be connected to establish a signal communicationbetween the camera assembly 6 of the endoscope 1 and the monitor 11.

The proximal-distal direction PD is an axis extending along the parts ofthe insertion tube 3 of the endoscope 1.

According to the method of the first embodiment disclosed herein, thetip part assembly 5 is manufactured by the steps of: a) providing abendable bending section 4 which includes a proximal end 4 a and adistal end 4 b, b) providing a camera assembly 6 comprising a cameramodule 60 and a circuit board 70 in electrical connection with eachother, c) providing a substantially tubular circumferential wall 8 g,the circumferential wall 8 g comprising a proximal end 8 a and a distalend 8 b, the circumferential wall proximal end 8 a being positionedoppositely from the circumferential wall distal end 8 b, d) providing adistal end wall 8 e, 8 e′, 8 e″, 8 e′″, e) arranging the camera module60 so that the camera module 60 is held by or attached to the distal endwall 8 e, 8 e′, 8 e″, 8 e′″, f) subsequent to step e), manufacturing ahousing 8, 8′, 8″ of the tip part assembly 4 by adjoining the distal endwall 8 e, 8 e′, 8 e″, 8 e′″ to the distal end 8 b of the circumferentialwall 8 g so that the housing 8, 8′, 8″ comprises the circumferentialwall 8 g and the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ and so that thecircumferential wall 8 g and the distal end wall 8 e, 8 e′, 8 e″, 8 e′″enclose a spacing, at least a portion of the camera module 60 beinghoused in the spacing, and g) subsequent to step f), adjoining thedistal end 4 b of the bending section 4 and the proximal end 8 a of thehousing 8, 8′, 8″, so that the tip part assembly 5 comprises the bendingsection 4, the camera assembly 60, and the housing 8, 8′, 8″, the cameraassembly 60 being at least partly housed in the spacing, the distal endwall 8 e, 8 e′, 8 e″, 8 e′″ being positioned at the distal end 5 b ofthe tip part assembly 5.

Alternatively, the tip part assembly 5 may be manufactured according tothe method of the second embodiment which shares steps a)-b) with thefirst embodiment and comprises the following steps of: c) extruding asubstantially tubular circumferential wall 8 g, the circumferential wall8 g comprising a proximal end 8 a and a distal end 8 b, thecircumferential wall proximal end 8 a being positioned oppositely fromthe circumferential wall distal end 8 b, d) providing a distal end wall8 e, 8 e′, 8 e″, 8 e′″, e) arranging the camera module 60 so that thecamera module 60 is held by or attached to the distal end wall 8 e, 8e′, 8 e″, 8 e′″, f) manufacturing a housing 8, 8′, 8″ of the tip partassembly 5 by adjoining the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ tothe distal end 8 b of the circumferential wall 8 g so that the housing8, 8′, 8″ comprises the circumferential wall 8 g and the distal end wall8 e, 8 e′, 8 e″, 8 e′″ and so that the circumferential wall 8 g and thedistal end wall 8 e, 8 e′, 8 e″, 8 e′″ enclose a spacing, and g)adjoining the distal end 4 b of the bending section 4 and the proximalend 8 a of the housing 8, 8′, 8″, so that the tip part assembly 5comprises the bending section 4, the camera assembly 6, and the housing8, 8′, 8″, the camera assembly 6 being at least partly housed in thespacing, the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ being positioned atthe distal end 5 b of the tip part assembly 5.

Another embodiment of this disclosure concerns a method according to thefirst embodiment, wherein the method is also according to secondembodiment. The steps a) to g) of the first embodiment may overlap orcorrespond to the steps a) to g) of the second embodiment.

Turning to FIG. 2 , a plane view of the bending section 4 is provided.The bending section 4 allows the tip part assembly 5 to bend relative tothe insertion tube 3, so as to allow an operator to manipulate the tippart assembly 5 while inserted into a body cavity of a patient. Thebending section 4 is molded in one piece, but may alternatively beconstituted by a plurality of molded pieces. The bending section 4comprises a number of hingedly connected segments including a distal endsegment 41, a proximal segment 43, and a plurality of intermediatesegments 42 positioned between the distal end segment 41 and theproximal segment 43. The distal end segment 41 is adapted for beingconnected and/or attached to a housing 8, 8′, 8″ of a tip part assembly,such as the housing 8, 8′, 8″, of FIGS. 4A-4F at a proximal end 8 a ofthe housing 8, 8′, 8″. An adhesive is separately applied to adjoin thebending section end segment 41 to the housing 8, 8′, 8″.

FIG. 3 shows a perspective view of the camera assembly 6 which is asub-assembly of the tip part assembly 5 and comprises camera module 60 acircuit board 70, and a substantially box-shaped camera module housing60 c. Inside the camera module housing 60 c an image sensor (not shown)and a stacked lens stack (not shown) is arranged. The lens stack ispositioned distally of the image sensor and includes a proximal lens anda distal lens. The camera module 60 further comprises a lens barrel (notshown) extending in the longitudinal direction, and which holds andencases the lens stack. The camera module 60 extends in the longitudinaldirection L.

The circuit board 70 is electrically connected to the camera module 60through a proximal connection surface 60 d at a proximal end 60 d of thecamera module 60. The circuit board 70 is a printed circuit board (PCB).Alternatively, the circuit board 70 could be a flexible printed circuit(FPC)

Turning to FIGS. 4A-4F, different embodiments of the tip part assemblyare shown. The housing 8, 8′, 8″ is manufactured by adjoining acircumferential wall 8 g and a distal end wall 8 e, 8 e′, 8 e″, 8 e′″.The housing 8, 8′, 8″ provides electrical insulation and water tightnessaround the camera assembly 6 and electrical connections within thehousing 8, 8′, 8″. The housing 8, 8′, 8″ also ensures that a minimuminsulation thickness is present on all outer surfaces of the tip partassembly 5.

The circumferential wall 8 g is cylindrical and has constant circularcross-sectional profile. The wall 8 g is an outer wall and defines anouter surface of the tip part assembly 5 for facing the environment. Noparts of the tip part assembly 5 are positioned outside an outercircumference of the circumferential wall 8 g. Manufacture of thecircumferential wall 8 g includes extrusion of the circumferential wall8 g through a die which has a ring-shaped cross section and cutting theextruded circumferential wall 8 g to length.

The length in a longitudinal direction of the circumferential wall 8 gis 10 mm and has a wall thickness of 0.15 mm. The outer maximum extentin a cross-sectional direction, which is the outer maximum diameter ofthe circumferential wall 8 g, is less than 3.3 mm.

In some embodiments step d) of the first or second embodiment comprisesextruding the circumferential wall part and, subsequently, cutting apiece off of the circumferential wall part so that the piece constitutesthe circumferential wall 8 g. The circumferential wall part is acircumferential wall blank.

The circumferential wall 8 g extends to cover a bending section distalend segment 41 and is bendable, allowing the circumferential wall 8 g tofollow bending of the bending section 4.

The circumferential wall 8 g is provided separately from the distal endwall 8 e, 8 e′, 8 e″, 8 e′″ before it is adjoined with the distal endwall 8 e, 8 e′, 8 e″.

In step e) of the methods of this disclosure, the circumferential wall 8g is positioned such that the it does not enclose the camera module 60,the camera assembly 6, or any other components of the tip part assembly5, which allows for more space around the camera module 60 and distalend wall 8 e, 8 e′, 8 e″, 8 e′″ during step e).

The distal end wall 8 e, 8 e′, 8 e″, 8 e′″ is provided in step d) as apart separate from the circumferential wall 8 g, i.e. not in one piecewith the circumferential wall 8 g and is molded.

The electrical connection between the circuit board 70 and the cameramodule 60 is established in step b). Alternatively, it may beestablished during or after any one of steps e), f), and g).

As seen in FIGS. 4A-4F, the distal end wall 8 e, 8 e′, 8 e″, ispositioned at the distal end 5 a of the assembled tip part assembly 5.The distal end wall 8 e, 8 e′, 8 e″, 8 e′″ comprises a holding section 8h for holding the camera module 60 as seen in FIGS. 5A-6B. In step e) ofthe methods of this disclosure, the camera module 60 is attached andheld in the holding section 8 h. The holding section 8 h includes anopening 8 i which is shaped to correspond to the outer surface of thecamera module 60 at the distal end 60 b of the camera module 60, in thedistal end wall 8 e, 8 e′, 8 e″, 8 e′″. The camera module distal end 60b is arranged in the opening 8 i in step e), by sliding the cameramodule distal end 60 b into the opening 8 i, from a proximal end of theopening 8 i in a distal direction. The camera module 60 may be held inthe camera holding aperture/section by friction, initially, until theadhesive secures the camera module 60 in the spacing. The cameraassembly may comprise a front lens/window attached to the barrel that isexposed, through the camera holding aperture/section, to the bodycavities, best shown in FIGS. 4E, 4F, and 5A-C.

Alternatively, the distal front surface of the camera module 60 isprovided proximally of the distal end wall 8 e, 8 e′, 8 e″, 8 e′″adjacent to distal end wall proximal surface such as in the embodimentshown in FIG. 4A. Here the distal end wall 8 e does not include a cameramodule opening 8 i, but rather extends in front of the camera moduledistal end surface. In this case, the distal end wall 8 e is transparentto allow light to shine through the distal end wall 8 e into the cameramodule 60. This also applies to the distal end wall 8 e′ in FIG. 4B.

In a final position of the camera module 60, a camera module frontsurface, which is a distal lens front surface (not shown), is plane witha distal end wall distal surface. Alternatively, the distal lens frontsurface may be positioned at a distance from the distal end wall distalsurface in the final position of the camera module 60. To aid fixationof the camera module 60 relative to the distal end wall 8 e, 8 e′, 8 e″,8 e′″ an adhesive is applied into a slot between the camera moduledistal end 60 b and the opening 8 i. This adhesive is applied togetherwith an adhesive applied within the spacing.

The circumferential wall 8 g and the distal end wall 8 e, 8 e′, 8 e″, 8e′″ are of an electrically insulating and transparent material. Thecircumferential wall 8 g consists of acrylic and the distal end wall 8e, 8 e′, 8 e″, 8 e′″ consists of polycarbonate. They may alternativelyconsist of the same material.

Adjoining of circumferential wall 8 g and the distal end wall 8 e, 8 e′,8 e″, 8 e′″ is performed by means of an adhesive, which is be appliedbetween an inner surface of the circumferential wall 8 g and outersurface of the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ facing the innersurface of the circumferential wall 8 g. The bending section 4 and thehousing 8, 8′, 8″ are adjoined by applying an adhesive to the distal endof the bending section 4 b and the proximal end of the housing 8 a. Theadhesive used to adjoin the distal end of the bending section 4 a andthe proximal end of the housing 8 a is the same type of adhesive as theone used to adjoin the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ and thecircumferential wall 8 g.

To secure the camera assembly 6 and the working channel 7 in the housing8, 8′, 8″, an adhesive 80 is filled into the spacing of the housing 8,8′, 8″ so that the camera assembly 6 is embedded in the adhesive 80 asseen in FIG. 4F. The adhesive 80 is then caused to harden, whereby theadhesive 80 attaches the housing 8, 8′, 8″ and the camera assembly 6 toeach other. Electronic wires (not shown) for connecting the circuitboard 70 to other parts of the endoscope are also partly embedded in theadhesive 80. This is advantageous since wires or cables may be pulledduring operation of the endoscope, pulling also in the circuit board 70,especially during bending of a bending section 4 of the tip partassembly 5. The adhesive is a liquid adhesive 80 with electricallyinsulating properties and is of a low dynamic viscosity below or equalto 200 cP (centipoise, which is equal to mPa's). This helps ensure thatthe adhesive 80 reaches substantially all corners of a free volume ofthe spacing.

The adhesive 80 is a silicone adhesive and is poured into the spacingthrough an open proximal end of the housing 8, 8′, 8″. To ensure acorrect amount of adhesive 80 is filled into the spacing in the housing8, 8′, 8″, an upper level 81 of the adhesive 80 is measured duringfilling. Alternatively, a predefined amount of adhesive may be measuredoff and poured into the spacing in the housing 8, 8′, 8″. The adhesive80 acts as a potting material and provides the tip part assembly 6 withgreater robustness, mechanical stability, and rigidity. To ensure theadhesive 80 is hardened and cured correctly it is heat cured after beingfilled into the spacing in the housing 8, 8′, 8″.

In some embodiments, the methods according to this disclosure mayfurther comprise the steps of: providing a working channel 7 of the tippart assembly 5; and arranging at least a portion of the working channel7 in the spacing.

The step of arranging at least a portion of the working channel 7 in thespacing is performed before the step of arranging the cameramodule/assembly and/or the step of adjoining the circumferential wall 8g and the distal end wall 8 e, 8 e′, 8 e″, 8 e′″.

As seen in FIGS. 4B-4F the second and third embodiment include a workingchannel 7 extending through the spacing of the housing 8′, 8″ to anopening 7 c in the distal end wall 8 e′, 8 e″. The working channel 7further extends into the distal end segment 41 and the bending section 4and proximally through the insertion tube 3. The working channel 7allows liquid to be removed from a body cavity and insertion of surgicalinstruments or the like into the body cavity. A connecting portion (notshown) is provided at the proximal end of the endoscope 1 a to allowinsertion of a tool into the working channel 7 and to allow suction tobe applied to the working channel 7. In some embodiments, the workingchannel 7 comprises a built-in or integrated tool at or in the distaltip part assembly 5. Such a tool may be suitable for grabbing, taking,and/or holding elements in a part of a patient, in which the endoscopetip part is arranged during use.

As shown, the working channel 7 is tubular and has a circumferentiallyextending tubular circular cylindrical outer wall enclosing a workingchannel spacing. The material thickness of the tubular wall is less than0.15 mm. The working channel 7 has an inner diameter of 1.2 mm.Non-circular outer walls are also permissible, e.g. oval.

Returning to FIGS. 5A and 5B, similar to a holding section 8 h for thecamera module 60, the distal end wall 8 e, 8 e′, 8 e″, 8 e′″ comprises aholding section 8 j for holding the working channel 7, the camera module60 being held in the holding section 8 h during positioning of theworking channel 7. The holding section 8 j for the working channel 7similarly includes an opening 7 c in the distal end wall 8 e, 8 e′, 8e″, 8 e′″, which opening 7 c is shaped to correspond to an outer surfaceof the working channel 7 c at a distal end of the working channel 7 c.The working channel distal end is arranged in the opening 7 c by slidingthe working channel distal end into the opening 7 c, from a rear orproximal end of the opening 7 c in the longitudinal, distal direction L.The working channel holding section 8 j may comprise a holding bracketand a backstop as disclosed for the camera module holding section 8 h.Like the camera module 60, the working channel 7 is attached in theholding section 8 j by an adhesive. This adhesive is applied togetherwith the adhesive applied in connection with the camera module 60 asdisclosed above. The adhesive is applied along a periphery of theworking channel 7 c.

As best seen in FIGS. 5B and 5C, the distal end wall 8 e″ comprises adistal wall section 8 k and an internal section 8 l extending proximallyfrom the distal wall section, wherein the distal wall section and theinternal section comprise a camera module opening 8 i sized and shapedto match a size and shape of the camera module, and wherein at least aportion of the camera module is received by the camera module opening 8i. The internal section 8 l fits within and is affixed to the internalsurface of the circumferential wall during assembly. LEDs 9 and lightguides 50 (shown in FIGS. 6A and 6B) may be affixed to the internalsection 8 l. The light guides 50 may also be molded in one piece withthe distal end wall 8 e″. The LEDs 9 may be electrically connected tothe circuit board 70 to receive power therefrom, in any known manner.The distal end wall 8 e″ may be transparent to allow light emitted fromthe LEDs 9 to illuminate the field of view of the camera module.

The holding section 8 j comprises a longitudinal wall extendingproximally from the distal end wall 8 e, 8 e′, 8 e″, 8 e′″. As shown inFIGS. 5B and 5C, the longitudinal wall may be cylindrical and comprisesa cut-out 8 m adjacent, when the distal tip is assembled, the cameramodule 60. At a location opposite the cut-out 8 m, denoted by numeral 8p, the wall thickness of the longitudinal wall is reduced. The cameramodule opening and the working channel/tube holding section define avertical extent 80 of the housing. The working tube holding sectioncomprises opposite wall sections 8 n parallel to the vertical extentwhich are thicker than a wall section 8 p traversing or adjacent thevertical extent. The design of the cut-out and thinner wall thicknessreduce the cross-section of the tip part assembly and enable manufactureof an endoscope with a smaller insertion section. The working tubeholding section can additionally include a longitudinal cut-out inaddition to or in lieu of thin wall section 8 p. The upper and lowerlongitudinal cut-outs are sized and shaped to reduce a distance betweenthe camera module and the lower portion of the circumferential wall ofthe housing (e.g. a distance that includes the diameter of the workingchannel/tube holding section) by minimizing the distance between thecamera module and the working channel/tube holding section and alsobetween the working channel/tube holding section and the circumferentialwall, thus enabling production of an endoscope with a very smallcross-section. In addition to the cut-outs, the surfaces of thelongitudinal wall forming the working channel/tube holding sectionadjacent at least the camera module are flattened transversely to thelongitudinal extent, as shown in FIG. 5C, to further reduce thedistance.

Turning to FIGS. 6A and 6B, the tip part assembly 5 further includes twoLEDs 9 for illuminating a target of the endoscope 2 as seen in FIGS. 6Aand 6B. The LEDs 9 are positioned at the proximal end of light guides 50and are substantially embedded in the adhesive 80 with the exception ofa light emitting surface. The tip part assembly 5 also includes twolight guides 50, of which one is shown in FIG. 6A, for guiding lightfrom a respective LED 9 to a distal end surface of the end wall 8 e, 8e′, 8 e″, 8 e′″. In FIGS. 6A and 6B the light guides 50 are provided asseparate pieces from the distal end wall 8 e′″ and then attached tothereto. The light guides 50 are also separate from the circumferentialwall 8 g. It is also possible to mold the light guides 50 in one piecewith the distal end wall 8 e, 8 e′, 8 e″, 8 e′″. As shown in FIGS. 6Aand 6B, the housing of the tip part assembly is formed by adjoining thedistal end wall 8 e′″ to the distal end of the circumferential wall sothat the housing comprises the circumferential wall and the distal endwall. In this case a transparent portion 10 of the housing, formed withthe front wall, extends proximally from the front wall 8 e′″.

The tip part assembly 5 also comprises a steering section (not shown)for steering the light guides 50 that comprise light fibers. Thesteering section may be provided separately from the distal end wall 8e′″.

The following additional examples expand and further exemplify thefeatures described above:

-   -   (1) A method of manufacture of a tip part assembly for an        endoscope, the tip part assembly having a proximal end for being        connected to other parts of the endoscope and a distal end        positioned oppositely from the proximal end, the method        comprising the steps of: providing a bendable bending section,        the bending section including a proximal end and a distal end,        providing a camera assembly comprising a camera module,        providing a substantially tubular circumferential wall, the        circumferential wall comprising a proximal end and a distal end,        the circumferential wall proximal end being positioned        oppositely from the circumferential wall distal end, providing a        distal end wall, arranging the camera module so that the camera        module is held by or attached to the distal end wall,        manufacturing a housing of the tip part assembly by adjoining        the distal end wall to the distal end of the circumferential        wall so that the housing comprises the circumferential wall and        the distal end wall, and so that the circumferential wall and        the distal end wall enclose a spacing, at least a portion of the        camera module being housed in the spacing, and, adjoining the        distal end of the bending section and the proximal end of the        housing, so that the tip part assembly comprises the bending        section, the camera assembly, and the housing, the camera        assembly being at least partly housed in the spacing, the distal        end wall being positioned at the distal end of the tip part        assembly.    -   (2) A method of manufacture of a tip part assembly for an        endoscope, the tip part assembly having a proximal end for being        connected to other parts of the endoscope and a distal end        positioned oppositely from the proximal end, the method        comprising the steps of: providing a bendable bending section,        the bending section including a proximal end and a distal end,        providing a camera assembly comprising a camera module,        extruding a substantially tubular circumferential wall, the        circumferential wall comprising a proximal end and a distal end,        the circumferential wall proximal end being positioned        oppositely from the circumferential wall distal end, providing a        distal end wall, arranging the camera module so that the camera        module is held by or attached to the distal end wall,        manufacturing a housing of the tip part assembly by adjoining        the distal end wall to the distal end of the circumferential        wall so that the housing comprises the circumferential wall and        the distal end wall, and so that the circumferential wall and        the distal end wall enclose a spacing, and adjoining the distal        end of the bending section and the proximal end of the housing,        so that the tip part assembly comprises the bending section, the        camera assembly, and the housing, the camera assembly being at        least partly housed in the spacing, the distal end wall being        positioned at the distal end of the tip part assembly.    -   (3) A method according to (1), wherein the method is also        according to (2).    -   (4) A method according to (1) or (2), wherein providing a distal        end wall comprises extruding the circumferential wall part and,        subsequently, cutting a piece off of the circumferential wall        part so that the piece constitutes the circumferential wall.    -   (5) A method according to any one of (1)-(4), further comprising        the steps of:

providing a working channel of the tip part assembly; and arranging atleast a portion of the working channel in the spacing.

-   -   (6) A method according to any one of (1)-(5), further comprising        the step of:        -   filling a liquid adhesive into the spacing so that the            camera assembly is at least partly embedded in the adhesive.    -   (7) A method according to any one of (1)-(6), wherein an outer        maximum extent in a cross-sectional direction of the        circumferential wall is less than 3.3 mm.    -   (8) A method according to any one of (1)-(7), wherein the tip        part assembly further comprises at least one light guide.    -   (9) A tip part assembly for an endoscope, the tip part assembly        having a proximal end for being connected to other parts of the        endoscope and a distal end positioned oppositely from the        proximal end, the tip part assembly comprising: a bendable        bending section, the bending section including a proximal end        and a distal end, a camera assembly comprising a camera module,        and a housing comprising an extruded substantially tubular        circumferential wall, the circumferential wall comprising a        proximal end and a distal end, the circumferential wall proximal        end being positioned oppositely from the circumferential wall        distal end, the housing further comprising a distal end wall        positioned at the distal end of the tip part assembly, wherein        the distal end of the circumferential wall is adjoined to the        distal end wall so that the circumferential wall and the distal        end wall enclose a spacing of the housing, wherein the distal        end of the bending section is adjoined to the proximal end of        the circumferential wall, and wherein the camera assembly is        arranged to be at least partly housed in the spacing.    -   (10) A tip part assembly according to (9), further comprising a        working channel, wherein at least a portion of the working        channel is arranged in the spacing.    -   (11) A tip part assembly according to (9) or (10), wherein at        least the camera module is attached or adhered to the housing by        means of a hardened adhesive positioned within the spacing, the        camera module being at least partly embedded in the adhesive,        the adhesive being provided separately from the housing.    -   (12) A tip part assembly according to any one of (9) to (11),        wherein an outer maximum extent in a cross-sectional direction        of the housing is less than 3.3 mm.    -   (13) A tip part assembly according to any one of (9) to (12),        wherein the distal end wall further comprises at least one light        guide and/or at least one steering section for steering a light        guide.    -   (14) A tip part assembly for an endoscope, wherein the tip part        assembly is manufactured according to the method of any one        of (1) to (8).    -   (15) An endoscope comprising a tip part assembly manufactured        according to any one of (1) to (8) or a tip part assembly        according to any one of (9) to (14).

LIST OF REFERENCES

The following is a list of reference numerals used throughout thisspecification.

-   -   1 endoscope    -   11 monitor    -   12 cable socket    -   13 monitor cable    -   2 handle    -   21 control lever    -   3 insertion tube    -   3 a proximal end    -   3 b distal end    -   4 bending section    -   4 a bending section proximal end    -   4 b bending section distal end    -   41 distal end segment    -   42 intermediate segment    -   43 proximal segment    -   tip part assembly    -   5 a tip part assembly proximal end    -   5 b tip part assembly distal end    -   50 light guide    -   6 camera assembly    -   6 a camera assembly proximal end    -   6 b camera assembly distal end    -   60 camera module    -   60 a camera module proximal end    -   60 b camera module distal end    -   60 c camera module housing    -   60 d camera module connecting surface    -   7 working channel    -   7 c working channel hole or opening    -   70 circuit board    -   8 housing    -   8 a housing proximal end    -   8 b housing distal end    -   8 c outer surface    -   8 e distal end wall    -   8 e′ distal end wall    -   8 e″ distal end wall    -   8 e′″ distal end wall    -   8 f window    -   8 g circumferential wall    -   8 h camera module holding section    -   8 i holding section opening    -   8 j working channel holding section    -   80 liquid adhesive    -   81 adhesive level    -   9 light-emitting diode (LED)    -   L longitudinal direction    -   PD proximal-distal direction

The invention claimed is:
 1. A method to manufacture an endoscope, themethod comprising: providing a bending section including a proximal endand a distal end; providing a camera assembly comprising a cameramodule; providing a circumferential wall, the circumferential wall beingsubstantially tubular and comprising a proximal end and a distal endopposite from the proximal end, the circumferential wall comprising aninner surface and an outer surface opposite the inner surface; providinga distal end wall comprising a distal end wall outer surface, includinga distal end wall distal surface, and further comprising a distal endwall proximal surface opposite the distal end wall distal surface, thedistal wall further comprising a working tube holding section affixed toan extending proximally from a distal wall section, distal end walldistal surface exposed to the external environment; arranging the cameramodule and the distal end wall so that the camera module is held by orattached to the distal end wall; subsequent to arranging the cameramodule and the distal end wall, adjoining the distal end wall to thedistal end of the circumferential wall to form a housing having aspacing therein with at least a portion of the camera module positionedin the spacing; and adjoining the distal end of the bending section andthe proximal end of the circumferential wall, wherein a camera moduleopening and the working tube holding section define a vertical extent ofthe housing, and wherein the working tube holding section comprisesopposite wall sections parallel to the vertical extent and a wallsection between the opposite wall sections of the working tube holdingsection and traversing the vertical extent, the opposite wall sectionsand the wall section between them extending proximally from the distalend wall, and the opposite wall sections being thicker than the wallsection between them.
 2. The method of claim 1, further comprisingextruding the circumferential wall before providing the circumferentialwall.
 3. The method of claim 2, wherein extruding the circumferentialwall comprises extruding a tube and cutting the circumferential wallfrom the tube.
 4. The method of claim 1, further comprising inserting adistal end of a working tube into the working tube holding section, theworking tube extending from the working tube holding section through thebending section.
 5. The method of claim 1, wherein the distal end wallcomprises a single-piece part including the distal wall section and aninternal section extending proximally from the distal wall section,wherein the distal wall section and the internal section comprise thecamera module opening sized and shaped to match a size and shape of thecamera module, and wherein at least a portion of the camera module isreceived by the camera module opening.
 6. The method of claim 1, furthercomprising mounting a working tube over the working tube holding sectionprior to adjoining the distal end wall to the distal end of thecircumferential wall.
 7. The method of claim 1, wherein the working tubeholding section comprises a longitudinal cut-out traversing the verticalextent and located adjacent the camera module opening.
 8. The method ofclaim 1, further comprising positioning at least a portion of a workingchannel in the spacing of the housing.
 9. The method of claim 1, furthercomprising filling the spacing at least partially with a liquid adhesiveto at least partly embed the camera module.
 10. The method of claim 1,wherein an outer maximum extent in a cross-sectional direction of thecircumferential wall is less than 3.3 mm.
 11. The method of claim 1,wherein the endoscope further comprises at least one light guide. 12.The method of claim 1, wherein adjoining the distal end wall to thedistal end of the circumferential wall comprises applying an adhesivebetween the inner surface of the circumferential wall and the outersurface of the distal end wall.
 13. The method of claim 1, furthercomprising filling at least a portion of the spacing of the housing withan adhesive to at least partially embed the camera assembly in theadhesive.
 14. The method of claim 13, wherein filling the at least theportion of the spacing comprises inserting a predetermined amount of theadhesive.